Textures changing in render but not in 3D View
The textured view is a shortcut to see the texture mapping of the image in the UV editor window. I suppose your texture is applied to the material of your model: select the model, Tab into edit mode, select all vertices, open an UV editor window, close the image of the window (if present), load your texture.
In this way the texture is "attached" to the actual UV map and will be displayed in the 3D view.